The present invention relates to rotating vehicle seats that are designed so that passengers, such as elderly or handicapped persons, can easily get in or out of a vehicle.
A rotating seat of this type has been constructed to be rotated to the side of a door opening with an occupant held in a seated position (as disclosed, for example, in Japanese Laid-Open Utility Model Publication No. 61-57047 and Japanese Laid-Open Patent Publication No. 62-173343). The rotating vehicle seat is typically disposed as far to the rear as possible in order to provide a wide space close to the occupant""s feet. Therefore, the seats in the front and the rear, for example in a four-door sedan car, are disposed such that the seats are masked beside the center pillars and the rear pillars.
Therefore, if the seat is rotated while in the initial seated position, the pillar that is positioned beside the seat interferes with the rotation of the seat to the entry/exit position. Therefore, with the known rotating seat, the rotating seat is first moved forward in order to be moved outside of the range of interference with the pillar. Thereafter, the seat is rotated to the door opening side.
Thus, the known rotating seat is inconvenient to use because it requires troublesome operations of moving the rotating seat forward and then rotating it to the side of the door opening. Further, if the seat is positioned near the front, such that the seat can be rotated while in the seated position, the space close to occupant""s feet will be sacrificed and the occupant will be forced to sit in an uncomfortable position.
The present invention has been made in view of the above problems, and its object is to provide a rotating vehicle seat that is convenient to use without sacrificing the space close to the occupant""s feet.
To this end, the invention according to claim 1 provides a rotating vehicle seat that comprises a rotating support base for supporting a seat body in a manner that permits rotation around a center of rotation that is located at a point displaced to a door opening side with respect to a center of a seat cushion, a longitudinal support base for supporting the rotating support base to permit movement in a longitudinal direction of the vehicle, and coupling means for coupling the rotational movement and the longitudinal movement of the seat body, the coupling means including a pinion gear mounted beneath the seat body to the interior side of the center of rotation and a rack mounted on and extending in a longitudinal direction of the longitudinal support base, the rack engaging the pinion gear via an intermediate gear.
According to this rotating vehicle seat, when the seat body is rotated to the door opening side by means of the rotating support base, the seat body moves forward while rotating by engagement between the pinion gear and the rack via the intermediate gear. Therefore, even if the seat body is located in the rearmost position in order to provide a wide space close to the occupant""s feet, the seat body can rotate by a simple rotational operation to the door opening side without interfering with a pillar or other portions of the vehicle. In other words, unlike the known rotating seat, it is not necessary to perform two operations of rotating the seat body and moving the seat body forward. Consequently, with the rotating vehicle seat according to claim 1 of the invention, it is possible to greatly improve ease of use while providing a wider space close to the occupant""s feet.
Further, because the center of rotation of the seat body is located at a point that is displaced to a door opening side with respect to the center (HP: hip point) of the seat cushion, a pinion gear having a larger diameter can be mounted under the seat body to the interior side with respect to the center of rotation. Because the pinion gear having a larger diameter has a larger circumferential length, the distance of the longitudinal movement of the seat body, which is coupled to the rotational movement of the seat body, can be longer. Thus, the seat body can be moved a longer distance while rotating, for example, by about 90xc2x0. Therefore, the seated position of this rotating seat can be positioned more rearward so as to provide a wider space close to the occupant""s feet, so that this rotating seat can be reasonably applied to various types of vehicles.
The pinion gear having a larger diameter can be also mounted to the door opening side with respect to the center of rotation when the center of rotation of the seat body (rotating support base) is located to the interior side with respect to the center of the seat cushion. In this case, however, when the seat body is rotated to the door opening side, the center of the seat cushion is displaced rearward. Therefore, the center of rotation, which is located more to the interior side, makes it more difficult to move the center of the seat cushion a long distance forward. In this respect, with the construction according to claim 1, because the center of rotation is located to the door opening side with respect to the center of the seat cushion, the moving distance of the center of the seat cushion is a total of the forward displacement by the rotation of the seat body plus the forward moving distance of the rotating support base. Therefore, the center of the seat cushion can be moved a longer distance forward.
The invention according to claim 2 provides the rotating vehicle seat as defined in claim 1, further comprising a lateral support base for moving the seat body in a lateral direction of the vehicle and a stopper member for preventing longitudinal movement of the seat body during lateral movement of the seat body, wherein the stopper member is disposed on the longitudinal support base to permit movement into and out of a longitudinal travelling path of the seat body, such that the stopper member moves out of the travelling path of the seat body to thereby allow the seat body to move longitudinally when the longitudinal support base is moved to an interior side end of the lateral support base, while the stopper member moves into the travelling path of the seat body to thereby prevent longitudinal movement of seat body when the longitudinal support base moves from the interior side end to the exterior side of the lateral support base.
According to this rotating vehicle seat, unlike the known rotating seat, a stopper member for restricting the longitudinal movement of the seat body is disposed on the longitudinal support base and not on the lateral support base. Therefore, whether the longitudinal support base is moved by the lateral support base in a horizontal direction, or in an inclining direction as the known rotating seat, the seat body can be prevented from moving longitudinally while moving laterally with respect to the vehicle.
Further, in the known rotating seat, the stopper means was provided on the lateral support base and thus required a size change according to the lateral moving distance of the longitudinal support base, which is not desirable for simplifying the construction or reducing the weight of the present rotating vehicle seat. With the construction according to claim 2, because the stopper member is provided on the longitudinal support base that moves laterally, the construction can be made compact irrespective of the lateral moving distance of the longitudinal support base, and thus the weight can be reduced.
The invention according to claim 3 provides the rotating vehicle seat as defined in claim 1, further comprising a lateral support base for moving the seat body in a lateral direction of the vehicle, the lateral support base being disposed between the rotating support base and the seat body and being constructed to move the seat body to a lower position as the seat body moves to the outside in the lateral direction of the vehicle.
According to this rotating vehicle seat, because the lateral support base is rotated by the rotating support base, unlike a known lateral support base, the lateral support base moves to a position in which its longitudinal sides extend in the longitudinal direction of the vehicle. Therefore, when the rotating vehicle seat of this invention is applied to a passenger""s seat, a wider space can be provided between the passenger""s seat and the driver""s seat. Further, even if the motor is disposed on the rear end of the lateral support base in a manner to protrude from the lateral support base, the motor is moved to a position facing the rear seat. In this respect also, a wider space can be provided between the passenger""s seat and the driver""s seat. Thus, the space can be effectively utilized for various purposes, such as a passage to the rear seats.
The invention according to claim 4 provides the rotating vehicle seat as defined in claim 3, wherein the seat body can be detached from the lateral support base so as to be used as a wheelchair.
According to this rotating vehicle seat, the seat body can be-used separately as a wheelchair outside the vehicle, and when the seat body is connected as is to a lateral support base and moved into the vehicle, it can be also used as a passenger seat. Such a rotating seat does not require the wheelchair user to change from a vehicle seat inside the vehicle to a wheelchair outside the vehicle and vice versa, thereby making it easier for such a wheelchair user to enter and exit a vehicle.
Further, because the seat body can be used separately as a wheelchair and can be moved into the vehicle while maintaining the wheelchair function, the rotating seat is more convenient to use, compared with known rotating seats in which a wheelchair frame portion must be detached to use the seat body inside the vehicle.
Further, after having been used as a wheelchair, the seat body can be connected to the lateral support base by superposing and connecting the connecting base of the seat body on the inclined base. The inclined base is downwardly inclined toward the exterior side, and the connecting base is disposed parallel to the inclined base. With this construction, differences in the vertical position between the seat body and the lateral support base, if any, existing in the stage of moving the seat body as a wheelchair toward the lateral support base can be corrected by sliding contact between the connecting base and the inclined base that are parallel to each other. As a result, the seat body can be easily connected to the lateral support base.
On the contrary, in a known rotating seat, for example, a wheelchair is separated into a seat portion and a frame portion and only the seat portion is moved into a vehicle and used as a seat body. In order to move the seat body as a seat portion of the wheel chair, the seat body is moved along and between rails on the wheelchair frame and rails on the vehicle floor. In such a case, the vertical position of the rails on the wheelchair frame is required to correspond to the rails on the vehicle floor, and the difference in the vertical position of the seat body is not corrected, thereby requiring troublesome work in connecting the seat body.
The invention according to claim 5 provides the rotating vehicle seat as defined in claim 3, wherein the longitudinal support base and/or the lateral support base has a linear slide mechanism that consists of an outer rail, an inner rail and a plurality of steel balls disposed between the rails.
According to this rotating vehicle seat, the position of the fixed side or the moving side or both of one or both of the left and right linear slide mechanisms is adjusted in a direction perpendicular to the sliding direction. Thus, the force of pushing the steel balls 220c by the fixed rail and the moving rail in the linear slide mechanism 220 can be adjusted. Because a plurality of the steel balls are disposed between the V-shaped grooves, with the construction in which the fixed rail and the moving rail relatively push each other by an appropriate force, vertical and horizontal relative rattling of the rails can be prevented. As a result, the lateral support base and/or the longitudinal support base can slide smoothly without rattling.
The invention according to claim 6 provides the rotating vehicle seat as defined in claim 1, further comprising a swing extending mechanism that essentially consists of a quadric link mechanism, wherein the seat body can be moved laterally with respect to the vehicle by the swing extending mechanism and wherein the seat body can be detached from the swing extending mechanism so as to be used as a wheelchair.
According to this rotating vehicle seat, a wheelchair user can get in or out of the vehicle while he or she remains sitting in the wheelchair. Further, after the wheelchair user gets out of the vehicle while he or she remains sitting in the wheelchair inside the vehicle, the wheelchair can be detached from the lift-up mechanism and used in the same manner as a normal wheelchair. Therefore, unlike a known rotating seat, the wheelchair user does not need to change from a vehicle seat to a wheelchair or vice versa in the outside of the vehicle when getting into or out of the vehicle, thereby making such a wheelchair more convenient to use.
Particularly, the wheelchair can be connected as a whole, keeping the seat frame and the wheels as well as the seat section, to the lift-up mechanism so as to be moved between the inside and the outside of the vehicle. Therefore, the wheelchair user or the helper is only required to perform a simple operation of connecting the lift-up mechanism. Additional operations, such as separating the wheelchair into the seat section and the frame section, are not required. Also in this respect, such a wheelchair is more convenient to use.
Further, with a known construction in which the wheelchair is separated into the seat section and the frame section and only the seat section is moved into the vehicle, it is necessary to load the separated frame section separately into the vehicle. However, such labor is not necessary with a construction as described in claim 6 in which the whole wheelchair is moved and installed in the vehicle compartment. Also in this respect, the wheelchair is convenient to use, particularly for passengers"" helpers, and the usability of the vehicle rotating seat can be improved.
In this specification, retaining the sitting attitude of the wheelchair means to retain the attitude of the wheelchair on the road. The attitude of the wheelchair means the attitude (orientation) of the wheelchair in which the wheelchair user sitting in the wheelchair can retain the sitting attitude comfortably without falling down or otherwise being injured.
Further, the state in which the vehicle chair xe2x80x9ccan be used separatelyxe2x80x9d as a wheel chair refers to the state in which the vehicle chair has at least a seat section (seat body) and travelling wheels and can be used as a normal wheelchair.
The invention according to claim 7 provides the rotating vehicle seat as defined in claim 1, further comprising a swing extending mechanism that essentially consists of a quadric link mechanism, wherein the seat body can be moved laterally with respect to the vehicle by the swing extending mechanism and wherein the seat body can be detached from the swing extending mechanism so as to be used as a seat of a wheelchair.
According to this rotating vehicle seat, the seat holder with the seat body mounted thereon, can be moved by the lift-up mechanism from the vehicle compartment floor to the outside of the vehicle and vice versa, and can function as a seat section of the wheelchair when detached from the lift-up mechanism. Therefore, while sitting in the seat body, the passenger can move with the seat holder onto the seat frame of the wheelchair which is standing by outside the vehicle. Also, the passenger can move with the seat holder from the wheelchair into the vehicle while sitting in the seat body. As a result, the passenger""s helper does not need to help the passenger to transfer from and to the wheelchair, so that the labor of the helper can be greatly reduced.
Further, because the seat body forms the seat section of the wheelchair together with the seat holder, the ride comfort of the wheelchair can be improved.
Additionally, the connecting and disconnecting structure of the seat holder is very simple in construction, which consists of the seat holder, the anchor plates, the lock bolts and the lock knobs. Therefore, such a structure can be readily applied to existing lift-up mechanisms.
The invention according to claim 8 provides the rotating vehicle seat as defined in claim 1, further comprising a swing extending mechanism that essentially consists of a quadric link mechanism, wherein the seat body can be moved laterally with respect to the vehicle by the swing extending mechanism and wherein an electric motor is used as a driving source for the swing extending mechanism, the motor having a threaded shaft oriented to the front of the seat.
According to this rotating vehicle seat, the threaded shaft of the ball screw is not directed to the rear of the seat, so that the threaded shaft is not offensive to an occupant sitting in a seat that is behind the rotating seat. With this construction, when the electric motor of the actuator is actuated, the threaded shaft is rotated and the nut is moved relatively with respect to the threaded shaft. However, because the nut is connected to the vehicle floor side, the threaded shaft and thus the actuator eventually move themselves and the quadric link mechanisms are extended and retracted.
The invention according to claim 9 provides the rotating vehicle seat as defined in claim 1, further comprising a swing extending mechanism that essentially consists of a quadric link mechanism, wherein the seat body can be moved laterally with respect to the vehicle by the swing extending mechanism, and further comprising a swing lock mechanism that functions only when an impact is applied while the vehicle is running, so as to prevent the seat body from moving forward with respect to the vehicle by the swing extending mechanism, while, in normal operations when the vehicle is stopped, permitting the seat body to be moved laterally with respect to the vehicle.
With this rotating vehicle seat, when a strong impact is exerted on the vehicle by abrupt deceleration of the vehicle, swinging movement of the seat body is prevented by the swing lock mechanism.
In the normal extending operations when the vehicle is stopped, if the swing extending mechanism is actuated to start to slowly extend the seat body to the outside, the swing lock mechanism is released by coupling with the movement of the seat body. On the other hand, in the process of returning the seat body from the exterior side to the interior side by the reverse swinging movement of the swing extending mechanism, the swing lock mechanism is automatically locked when the seat body has been returned to a predetermined position in the vehicle. Thus, by coupling with the swinging movement of the seat body, the swing lock mechanism is automatically locked and unlocked. The swing locked state can be maintained irrespective of the sliding position by the slide mechanism which is separately set as necessary. Therefore, while maintaining the swing locked state, the position of the seat body in the longitudinal direction of the vehicle can be adjusted by utilizing the slide mechanism.
Further, when abrupt impact is exerted on the seat body, the swing locked state can be maintained, so that the load onto the seat body can be transmitted to the vehicle floor.
Further, because the swing locked state can be maintained irrespective of the lateral sliding position, the swing lock mechanism of this embodiment can be applied irrespective of whether a lateral slide mechanism is provided or not.
The invention according to claim 10 provides the rotating vehicle seat as defined in claim 1, further comprising a swing extending mechanism that essentially consists of a quadric link mechanism, wherein the seat body can be moved laterally with respect to the vehicle by the swing extending mechanism, and further comprising a swing lock mechanism that functions to prevent the seat body from being moved forward with respect to the vehicle by the swing extending mechanism when the seat body is located in a position facing the front of the vehicle, while permitting the seat body to be moved laterally with respect to the vehicle by the swing extending mechanism when the seat body is rotated to the door opening side.
With this rotating vehicle seat, when the seat body is rotated to the position facing the front of the vehicle, the swing lock mechanism is locked by being coupled to this rotational movement of the seat body. And when the seat body starts to rotate to the door opening side, the swing lock mechanism is automatically unlocked by coupling with this rotational movement of the seat body. Thus, the swing lock mechanism is locked and unlocked by coupling with the rotational movement of the seat body. Therefore, unlike a known rotating seat, the users do not need to manually operate the swing lock mechanism, so that the usability of the rotating vehicle seat of this embodiment can be improved.
Further, the lock holder is engaged with the lock plate by physical engagement between the lock holder and the anchor hook. Therefore, as long as the seat body is held in the position facing the front of the vehicle, the seat body can be reliably maintained in the swing locked state, even in the event of occurrences generating a large impact or vibrations. However, if it is constructed, for example, such that a biasing force of a spring is used to maintain the engagement of the lock holder with the lock plate, when a strong impact or vibrations are exerted on the vehicle, the lock holder may be rotated against the biasing force of the spring by the inertial force, so that the swing lock may be released. With the construction of the invention as described in claim 10, there is no possibility of such occurrences.
The invention according to claim 11 provides the rotating vehicle seat as defined in claim 1, wherein the longitudinal support base includes a linear slide mechanism that consists of a fixed rail, a moving rail and a plurality of rolling elements disposed between the fixed rail and the moving rail, and wherein a guide rail is provided on and along one side of the moving rail, which is opposite to the side of the fixed rail and supports the moving rail to permit the moving rail to slide.
With this rotating vehicle seat, a guard rail is provided on and along the inner side of the inner rail in parallel to the outer rail to permit the inner rail to slide. Thus, the deformation of the inner rail can be minimized and the removal of the rolling elements can be prevented, so that the longitudinal movement of the linear guide mechanism can be maintained with stability.
The invention according to claim 12 provides the rotating vehicle seat as defined in claim 11, further including a hook that is provided on a travelling path of the moving rail such that a rear end portion of the moving rail can slide into and out of the hook.
With this rotating vehicle seat, the inner rails can be prevented from being raised by a belt load that will act on the seat belt in the event of hard braking or a collision when the vehicle is running. Further, the belt load can be absorbed via the hook to the floor side, so damage to the linear guide mechanism can be prevented.
The invention according to claim 13 provides the rotating vehicle seat as defined in claim 1, wherein a toothless portion is formed on an initial engagement portion of the intermediate gear and a deformed tooth is formed on an initial engagement portion of the pinion gear and engages the toothless portion, the deformed tooth having a thickness substantially corresponding to a length of the toothless portion, a height of the deformed tooth on a front end in a direction of starting engagement being smaller than normal teeth, and a height of the deformed tooth on a rear end in the direction of starting engagement being equal to normal teeth.
With this rotating vehicle seat, when the seat body is rotated to the door opening side (in the engagement starting direction), at the stage when the pinion gear starts to engage the intermediate gear, that is, when shifting from the non-coupling state to the coupling state, because the deformed tooth of the pinion gear first engages the intermediate gear and the height of the deformed tooth on the front end in the engagement starting direction is smaller than normal teeth, the deformed tooth engages the toothless portion of the intermediate gear without interfering with the tooth on the rearward side of the toothless portion in the engagement starting direction. Thus, the pinion gear smoothly engages the intermediate gear.
On the other hand, when the seat body rotates from the door opening side to the interior side to be returned to the position facing to the front of the vehicle (when rotated in the direction opposite to the engagement starting direction), at the stage of finishing the engagement between the pinion gear and the intermediate gear, that is, when shifting from the coupling state to the non-coupling state, because the deformed tooth of the pinion gear last engages the intermediate gear and the height of the deformed tooth on the rear end in the engagement starting direction is equal to normal teeth. Thus, the pinion gear securely engages the intermediate gear. Therefore, the engagement (coupling state) between the pinion gear and the intermediate gear is maintained all the way, and thus the seat body can be reliably returned to the rear end sliding position.
Further, because the seat body can be reliably returned to the rear end sliding position, in the case of using a slide lock mechanism that is coupled to the rotational movement of the seat body, the slide lock mechanism can function properly and reliably.